Below is a list of organisations that can help with mental health issues.

Combat StressEstablished in May 1919, it is the UK’s leading charity for veterans’ mental health. Helps former service personnel deal with issues like trauma, anxiety, depression and post-traumatic stress disorder.
Help for HeroesEstablished in 2007. Supports those with injuries and illnesses sustained while serving in the British Armed Forces. Provides mental health support through its Hidden Wound service.
Walking with the WoundedEstablished in 2010. Supports a pathway for vulnerable veterans to re-integrate back into society and sustain their independence. At the heart of this journey is employment.
Big White WallIs an online mental health and well-being service offering self-help programmes, creative outlets and a community that cares.
National Health Service (NHS)Outline of mental health services available.
Ministry of Defence (MOD): GuidanceGuidance regarding mental health support for the UK armed forces.
Ministry of Defence (MOD): The Veterans & Reserves Mental Health ProgrammeGuidance regarding mental health support for the UK armed forces.
Mental Health FoundationTheir mission is to help people understand, protect and sustain their mental health.
PTSD ResolutionProviding counselling for former armed forces, reservists & families.
Scottish GovernmentSets out the Scottish Government position regarding armed forces and veterans’ healthcare.